Modular portable computer

ABSTRACT

A modular computer has a framework with module bays for receiving CPU modules, power modules, and peripheral function modules such as floppy and hard disk drives. The framework has a built-in compressed bus and a variety of function modules which can be plugged into any one of the module bays. Function modules include, but are not limited to, CPU, power, floppy disk, hard disk, RAM memory, LAN communication, modem, FAX communication, and data acquisition. In some embodiments function modules are provided for communicating with separate input means, such as voice, keyboards, and pen-pads. In one aspect the module bays and the function modules are configured according to dimensional and connective standards of the Personal Computer Memory Card International Association.

CROSS REFERENCE TO RELATED DOCUMENTS

This application is a continuation-in-part of application Ser. No.08/097,946, filed Jul. 26, 1993, now issued as U.S. Pat. No. 5,278,730,which is continuation of application Ser. No. 07/905,480, filed Jun. 29,1992, abandoned.

FIELD OF THE INVENTION

The present invention is in the area of portable computer systems, andis particularly relevant to portable computers known as notebook,sub-notebook, and palmtop computers.

BACKGROUND OF THE INVENTION

Portable computers are popular among computer users who travel and needto take their work along, and there is a tendency in the marketplace tosmaller and smaller versions of portable computers. They are smaller andlighter than laptops, and are therefore more portable. The evolution tosmaller and lighter portable computers, however, is not withoutproblems. For one thing, smaller portable computers means less space forbattery packs, which usually means shorter useful life betweenrecharges. Another problem related to smaller size is a difficulty inproviding versatility. Smaller size naturally means less space toprovide a broad choice in peripheral devices and options.

Yet another problem is related to addresses and data byte size.State-of-the-art computers are capable of 32 bit addresses and 32 bitdata words. A 32 bit computer, though, typically needs a bus structurewith nearly 100 active signals, equating to high pin count and extensivedevice and component density. Such high density in a small computercreates many other problems, such as problems with heat dissipation.These are a few of the many problems in designing and developingportable computers.

What is needed is a new design for portable computers based on a busstructure allowing 32-bit capability with a minimum pin count,utilizing, for example, multiplexing of address and data on a single 32bit structure, and utilizing only state-of-the-art technology tominimize power (hence buffer) requirements, which also minimizes heatand equipment complexity and density problems. Also, modularity needs tobe raised to a new level by making virtually all components modular and"plug-in", including CPU's, power packs, anti all of the various knownsorts of peripheral devices.

SUMMARY OF THE INVENTION

In a preferred embodiment of the invention a modular computer isprovided, comprising a case having contiguous walls, the case forsupporting and enclosing elements of the modular computer; a pluralityof separate module bays in a common plane, each module bay comprising awalled cavity in the case having an open outboard end and an inboard endclosed by an end wall, wherein the walls of each cavity, including theend wall, comprise an extension of the contiguous walls of the case; amulti-pin electrical connector mounted through the inboard wall of eachmodule bay; an internal bus within the contiguous walls of the caseconnected to each of the electrical connectors mounted through theinboard walls of the module bays; a display; and an input apparatusattached to the case substantially coplanar with the plane of the modulebays.

In one alternative embodiment the input apparatus is a keyboard, and thedisplay is pivoted to close over the keyboard. In another alternativeembodiment the display and the input apparatus comprise a touchscreencombination implemented on a surface of the enclosure. In someembodiments the docking bays have guides engaging guides of functionalmodules, and latching and expulsion apparatus to engage and expelfunctional modules.

In one preferred embodiment the input means is a keyboard, and thedisplay is a flat panel display hinged to the support structure, andclosable over the keyboard for storage and transport.

Functional modules are provided serving a wide variety of functions. Onemodule comprises a CPU, which provides flexibility in CPU type andpower, and upgradability as well. A CPU module may also incorporaterandom access memory and video display control. Function modules alsoare provided to enhance flexibility in input. Separate input devices,such as a full-size keyboard or a pen-based input tablet may be usedwith appropriate modules for receiving signals from the separate inputdevices and providing the signals to the internal bus. An input modulefor voice input, recognizing human speech, is also provided. Otherfunction modules include Fax modems, telephone modems, floppy drives,hard disk drives, LAN communication modules, and data acquisitionmodules.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an isometric view of a modular notebook computer frameworkaccording to an embodiment of the present invention.

FIG. 1B is a view of the computer framework of FIG. 1A from one sidefrom the vantage of line 1B--1B on FIG. 1A.

FIG. 2 is a sectioned plan view of the computer framework of FIG. 1Ataken according to section line 2--2 of FIG. 1B.

FIG. 3 is an isometric illustration showing a function module accordingto the present invention associated with a docking bay of the frameworkof FIG. 1A.

FIG. 4 is another view of a function module according to the presentinvention.

FIG. 5 is a block diagram of a compressed bus and connection to dockingbays in a computer framework according to an embodiment of the presentinvention.

FIG. 6 is a block diagram of a CPU function module according to anembodiment of the present invention.

FIG. 7 is a block diagram of a power supply function module according toan embodiment of the present invention, with indication of connectionsto the internal bus structure and power conversion unit of the computer.

FIG. 8 is a block diagram of a floppy disk drive function module used inthe invention.

FIG. 9 is a block diagram of a hard disk drive module used in anembodiment of the invention.

FIG. 10 is a block diagram of a "flash card" memory module according toan embodiment of the present invention.

FIG. 11 is a block diagram of a LAN module according to an embodiment ofthe present invention.

FIG. 12 is a block diagram of a modem module according to an embodimentof the present invention.

FIG. 13 is a block diagram of a FAX module according to an embodiment ofthe present invention.

FIG. 14 is a block diagram of a data acquisition module according to anembodiment of the present invention.

FIG. 15A is an isometric view of a modular palmtop computer frameworkaccording to an embodiment of the present invention.

FIG. 15B is a view of the computer framework of FIG. 15A from one sidefrom the vantage of line 15B--15B on FIG. 15A.

FIG. 16 is a sectioned plan view of the computer framework of FIG. 15Ataken along section line 16--16 of FIG. 15B.

FIG. 17 is an isometric illustration showing a function module and adedicated docking bay in an embodiment of the present invention.

FIG. 18 is another view of a function module according to an embodimentof the present invention.

FIG. 19 is a block diagram of a compressed bus and connection to dockingbays in a computer framework according to an embodiment of the presentinvention.

FIG. 20 is a block diagram of a CPU function module according to anembodiment of the present invention.

FIG. 21 is an isometric drawing of modular palmtop computer according toanother embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

General Description

FIG. 1A is an isometric drawing of a notebook computer framework 11according to the invention. Framework 11 comprises a back housing 13, atilt-up flat panel display 15, shown closed, a keyboard 17, and aplurality of module bays for plugging in function modules. Back housing13 includes a power unit for converting electrical input on a widevariety of standards to the form required by the computer. For example,there is a port (not shown) for connecting to a standard householdoutlet, rated at 120 V., 60 Hz, alternating current. The power unit willconvert the input to outputs as needed by the computer bus andfunctional modules. There are also input ports for 6 V. DC, 12 V. DC, 9V. DC, and others, and the power unit in one embodiment off the presentinvention is capable of recognizing the input characteristics bysampling, and switching to proper on-board circuitry to utilize theinput.

In the embodiment shown by FIG. 1A four module bays 19, 21, 23, and 25are shown along one side of the framework. There are four more modulebays along the other side of the framework opposite the module baysshown. There could be more or fewer module bays, but eight is convenientand a good balance between the need to stay small and simple, and toalso have adequate versatility.

FIG. 1B is an end view of the notebook computer framework of FIG. 1 inthe direction of arrows 1B--1B of FIG. 1A. Each of the module bays has aset of guide and positioning rails such as rails 27 and 29 in bay 19.The rails are to position and guide a function module inserted into themodule bay. Each rail in a set has a detent such as detent 31 forlatching a module when the module is fully inserted in the bay. Each bayalso has a connector such as connector 33 in bay 19. The connectors arefor coupling to a mating connector on a function module inserted in abay. It will be apparent to a person with skill in the art that thereare a number of equivalent ways guide rails, detents, and coupling maybe accomplished.

FIG. 2 is a plan section view just above the module bays taken alongsection line 2--2 of FIG. 1B. Bays 19, 21, 23, and 25 are shown on oneside of the section view, and bays 35, 37, 39, and 41 along the oppositeside. A printed circuit board structure 57 is fastened in asubstantially vertical position down the center of frame 59, andconnectors 33, 43, 45, 47.49, 51, 53, and 55 are connected to theprinted circuit board structure and present their pin structure outwardtoward the respective bay areas. In the presently described embodimentthe internal connectors are male connectors, but this is not arequirement of the invention.

As also shown in FIG. 1A, each module bay has a pair of opposed railslocated vertically at about the midpoint of the height of the modulebay. Rails 27 and 29 serve module bay 19, and similar rails are locatedin each of the other module bays.

FIG. 3 is an isometric view of a function module 61 according to theinvention aligned with module bay 25 of framework 11. Module 61 includesguides 63 and 65 on opposite sides for engaging rails 67 and 69 whenmodule 61 is inserted into bay 25. The module has two spring-loadeddetent levers (lever 73 is shown) for engaging detents in guide rails 67and 69 when the module is fully inserted. Detent 71 is shown in rail 67in FIG. 3.

Each module bay has a compression spring mechanism engaged by a functionmodule as the module nears full insertion, so there is an outward forceon the module when the detent levers engage the detents. Mechanism 75(FIG. 2) is exemplary. To insert a module one aligns the guides in themodule with the guide rails and pushes the module into the module bayuntil the detents engage. Button 79 on front face 77 of the module isfor retracting the detent levers of the module, in which case the springmechanism ejects the module, much as is the case with some floppy diskdrives.

FIG. 4 is an isometric view of function module 61, showing back face 81opposite front face 77. The back face includes a recessed femaleconnector receptacle 83 in the preferred embodiment, for mating withmale connectors positioned in each pod bay, such as connector 33 in FIG.1B and FIG. 2. A second detent lever 74 is opposite lever 73 of FIG. 3.

In the embodiment described above, and in many other embodiments, thenotebook computer framework of the present invention comprises a framewith module bays and connectors as described above for "plugging in"function modules, power supply units, and other peripheral devices. Theframework also comprises display 15, keyboard 17, and an internal busstructure hereinafter termed the Notebus, which is described inadditional detail below, in the section titled "Notebus Bus Structure".

The function modules, as represented by module 61 in FIG. 3 and FIG. 4,are provided in a wide variety of different models capable of a widevariety of different functions. For example, framework 11 has no"on-board" CPU, battery power, or system memory. These functions and allother functions are provided by different models of function moduleswhich may be inserted in any one or a combination of the availablemodule bays. Other kinds of function modules that may be insertedinclude floppy-disk drives, hard-disk drives, "flashcard" memorymodules, LAN and modem adapters, Fax modules, speciality modules such asdata acquisition modules adapted to specific equipment, and more. Thefunction modules are also described in more detail in the section belowtitled "Function Modules".

Electronic Architecture

FIG. 5 is a block diagram showing internal elements of Notebook computerframework 11, connected to show the electronic architecture of thenotebook computer according to the invention. Power input and conversionunit 85 is housed in back housing 13 (FIG. 1) and has ports 87 for powerinputs. Unit 85 senses the input conditions and selects appropriatecircuitry to convert the input to the voltages needed to power the otherelements of the system. Output from the conversion unit is to Notebus89, which comprises paths for power as well as for digital informationsuch as data and addresses.

Because there are a wide variety of function modules, as indicated aboveand described in more detail below, there needs typically to be morethan one power line in the Notebus. For example, the notebook computerof the invention comprises hard disk drive modules, and these modulesare preferably provided without their own "on board" power source. Themotor drive for the hard disk requires a different power (voltage andcurrent) than does a CPU, for example, so there are parallel power linesof differing size and voltage level in the notebus. A typical Notebuswill have, for example, a line for 24 V DC, another for 12 V DC, and yetanother for 5 V DC, as well as multiple ground lines.

Notebus 89 connects to a video display controller 91 including VideoRandom Access Memory (VRAM) which both powers and controls display 15,which in the preferred embodiment is a flat panel display driven byanalog driver lines on analog bus 93. Notebus 89 also connects to akeyboard controller 95 which powers and controls keyboard 17 over link97, accepting keystroke input and converting the input to digital datafor transmission on Notebus 89. The keyboard controller may bephysically mounted in the keyboard or in framework 11.

Notebus 89 also connects as illustrated in FIG. 5 to each of the modulebays, such as bay 19, through connectors, such as connector 33. When afunction module, such as module 61, is inserted into a module bay, themating connector in the back of the function module mates with theconnector from the Notebus, and circuitry inside the function module isthen connected to the Notebus.

Notebus Bus Structure

The Notebus comprises, as stated above, both power and data paths. Thedigital lines are capable of carrying 32 addresses and conveying data in32 bit word length. To minimize pin count and routing complexity,addresses and data are multiplexed on a single set of 32 traces in theoverall bus structure. One with skill in the art will recognize thatthis type of bus is what is known in the art as a low-pin-count orcompressed bus. In this kind of bus different types of signals, such asaddress and data signals, share signal paths through multiplexing. Forexample, the same set of data lines are used to carry both 32-bitaddresses and data words of 32-bit length.

In the Notebus of the present invention, some control signals, such asinterrupt arbitration signals, may also share the data lines. Typicalexamples of buses that are exemplary as usable for the Notebus (with theexception of power supply analog lines in the Notebus) are the "S-Bus"implemented by Sun Microsystems, the "Turbochannel" Bus from DigitalEquipment Corporation, and buses compatible with the IEEE-488 standard.

The Notebus is a high-speed backplane bus for interconnecting processor,memory and peripheral device modules. The Notebus also supplies standardoperating and standby power supply voltages and electrical ground to allmodule bays.

Function Modules

FIG. 3 and FIG. 4 show, as described above, two different views of afunction module according to the present invention. Also as statedabove, function modules may have many different functions. There are asmany different functions, in fact, as there are possibilities fordiscrete peripheral devices, plus power and CPU modules. An individualfunction module is provided for each function, and in each case thefunction module has a physical size and form compatible with the bays,guide rails, and connectors for "plugging in" to framework 11.

The "face" of a function module, being the exposed face when the moduleis "plugged in" (see face 77 in FIG. 3) may have elements specific tothe type of module. For example, a CPU module may have no indicators orother elements on the front face, while a floppy disc module willtypically have an opening for inserting a floppy disk and a "key" orbutton for releasing and ejecting the floppy disk.

A unique feature of the present invention is that the CPU for thenotebook computer is provided as a CPU function module. This provides anability for a user to tailor the CPU power to the other modules andapplication for the notebook computer, and an easy upgrade to morepowerful CPUs.

FIG. 6 is a diagram of a CPU module 99 plugged into a bay in a notebookcomputer according to the present invention. In this case (referring toFIG. 2) the module is plugged into bay 19 having connector 33. This isexemplary, as the module could just as well be plugged into any open bayof framework 11. By virtue of being plugged into connector 33 or anothermodule connector, internal elements of the CPU module are connected toNotebus 89.

The internal elements for module 99 comprise CPU 103, a state translator105, and RAM memory 113. CPU 103 may be any of a wide variety of CPUs(also called in some eases MPUs) available in the art, for example Intel80386 or 80486 models. MIPS, RISC implementations, and many others. CPU103 communicates with State Translator 105 over paths 107, and StateTranslator 105 communicates with connector 33, hence Notebus 89, overbus 109 internal to the module, which is an extension of bus 89 when themodule is plugged into bus 89.

State translator 105 is a chip or chip set designed to translatecommands and requests of the CPU to commands and requests compatiblewith the Notebus. It was mentioned above that CPU 103 may be one of awide variety of CPUs, and that. Notebus 89 may be any one of a widevariety of compressed buses. It will be apparent to one with skill inthe art that there may be an even wider variety of state translators 105for translating between the CPU and the Notebus. The state translator istheoretically a different device for each possible combination of CPUand Notebus.

RAM memory module 113 comprises conventional RAM chips mounted on a PCBas is known in the art, and connectable to state translator 105 by aplug or connector interface, such as an edge connector. The purpose ofhaving a RAM module "on board" the CPU module is to provide for rapidmemory access, which will be much slower if the RAM is made available ina separate module at one of the other module bays. Memory at anothermodule bay is on the Notebus, and will be subject to bus contention andwait states. The plug-in nature of the RAM unit relative to the CPUmodule allows different amounts of memory to be provided with a CPUmodule in the notebook computer of the present invention.

As described above, Notebus 89 comprises not only the shared data andaddress lines, but also power and ground connections for the modulesplugged into the various bays. Paths 109 and 107 therefore comprisepower and ground lines for CPU 103 and Translator 105.

If, for example, CPU 103 is an INTEL 80486 microprocessor, StateTranslator 105 will be a translator for accommodating the state machineof the 80486 to the state machine of the Notebus, which may be any oneof the buses described above for bus 89, or another compressed bus.There are many equivalent ways a translator may be implemented for thespecific case. Given the manufacturers available design information forthe CPU and the equivalent information for bus 89, it is within theskill of workers in the art without undue experimentation to implementthe translator and the required connections. This is conventionaltechnology. The implementation of the translator on a module with a CPUto plug into a module bay in the notebook computer is unique to thepresent invention.

In the invention, state translators may be implemented in a single chipset or circuitry set to be capable of translating between a number ofCPUs and a number of different bus possibilities. One might, forexample, design and implement a translator with the necessary circuitryand intelligence to translate between three different CPUs and threedifferent compressed buses. The state translator could be made hardwareor software programmable to select one CPU and one bus from theavailable selections at some convenient time in the manufacturing cycle,or even at the time of selection of modules to make up a notebookcomputer.

As an example of a hardware programmable translator, a translator couldbe built to have certain traces cut as a near final step in manufactureas a way of selecting the CPU and bus pair. Translators could also beprogrammable by virtue of on-board EPROM or EEPROM devices. As anexample of software programmability, translators could be implementedwith microprocessor technology and software programmable. A CPU modulecould be plugged into a connector on a special programming unit, forexample, before installation in a notebook computer according to thepresent invention, and be sent certain commands to set up on boardsoftware to translate between the desired CPU and bus. It will beapparent to one with skill in the art that there are many possiblevariations in the implementation of the translators.

FIG. 7 shows a power module 111 plugged into a bay in the notebookcomputer according to an embodiment of the present invention. Thepurpose of a power module is to provide a source of power for thecomputer, which includes any modules plugged into the module bays. As iscommon in notebook computers in the art, there may be a battery,typically rechargeable, in framework 11, and the battery may also bereplaceable and rechargeable through power input lines 87. In the caseof an on-board battery pack, there is the option of using all modulebays for other than power packs.

Preferably framework 11, sans function modules, has no power capabilityother than power plugged into one of input lines 87, which may beconverted to the power characteristics needed by the computer anddistributed on the power lines of the Notebus. For portability, power istypically supplied by one (or more) power modules 111 plugged into oneor more of the module bays.

Module 111 has a battery pack 101 which is connected via lines 117 to(in this case for example) connector 33, and hence to Notebus 89.Because there are several supply lines in the Notebus for supplyingpower to function modules at different voltage and with differentcurrent capability, the power lines in the Notebus For connecting apower module 111 are not the same as the lines for supplying power to amodule. There is instead a separate sat of power lines to pins on themodule bay connectors, such as connector 33, which connect as input, topower input and conversion unit 85, much as do input ports 87.

In FIG. 7, lines 119 and 121 connect power module 11 to conversion unit85, where the power input from the power module is sensed and treated asa power source, much as is done for power input lines 87. This power isconverted to the needed voltages and current capabilities, and put backout on the power supply output lines to the module bays. In FIG. 7 line119 is ground, and arrow 123 represents all of the data/address,control, and power output lines to the module bays. Lines represented byarrow 123, plus lines 119 and 121 are Notebus 89. Although not shown inFIG. 7, there are connections for line 119 and for line 121 to each ofthe module bay connectors.

Power modules such as module 111 may be plugged into a connector on acharging module separate from the notebook computer, using the sameconnector used for plugging into the Notebus via a module bay offramework 11, and recharged for later use with a modular notebookcomputer according to the invention. This allows a user to keep sparepower modules ready for use, and to recharge modules without connectingthe computer itself to a charging unit. Moreover, the provision of powermodules allows a user to provide more or less portable time to thenotebook computer by using one or more than one power module.

FIG. 8 shows a floppy disk drive (FDD) module 125 plugged into a modulebay in a notebook computer according to an embodiment of the presentinvention. Module 125 comprises a conventional FDD unit 129 for nominal3.5 inch disks with conventional circuitry mounted in a case 130 toprovide a module with guides, latches, and a connector matable withconnector 35 to be able to plug into a module bay in the notebookcomputer of the present invention. The case comprises an opening 131 forinserting and withdrawing a floppy disk, and an eject button 133 forejecting a floppy disk.

A controller 127 communicates with unit 129 over lines 126 and withconnector 33 (hence Notebus 89) over lines 128. The unit also derivespower from the appropriate pins on connector 33, but these pins andlines are not shown. Controller 127 is an ASIC chip or chip set fortranslating between the notebus and the FDD unit. Given the data storagestandards of the FDD unit and the characteristics of bus 89, it iswithin the scope of workers with ordinary skill in the art to implementcontroller 127 without undo experimentation.

FIG. 9 shows a hard disk drive (HDD) module 135 according to anembodiment of the present invention plugged into bus 89 in a module bayof framework 11. HDD module 135 comprises a conventional HDD unit 139mounted in a case 137 to be compatible with plugging into a notebookcomputer according to the present invention. As in the case of the FDDmodule described above, a controller 141 is provided to translatebetween Notebus 89 and the HDD unit. Controller 141 communicates withHDD unit 139 over lines 143, and with connector 33 over lines 145.Connector 33 is exemplary of any one of the module connectors in thenotebook computer.

Given the characteristics of HDD unit 139 and of Notebus 89, it iswithin the skill of workers in the art to implement controller 141without undue experimentation. Power line connections are not shown. Inimplementing controller 141 there are several protocols that may beused. One is the ST506 standard known in the art. Another is the IDEstandard known in the art. Yet another is an enhanced IDE, called EIDE,known to the inventors, and the subject of a separate patent applicationto be filed. In the EIDE protocol, there may be multiple IDE devicesdaisy-chained and addressed as secondary IDE devices with an additionalselect number.

FIG. 10 shows a "flash card" memory module 147 plugged into connector 33of the notebook computer of the invention. "Flash cards" are RAM memorycards known in the art pluggable into typically parallel ports o makeconnection with internal bus structures of a computer. Module 147comprises a conventional "flash card" 151 mounted in a case 149compatible with the module bay of a notebook computer according to thepresent invention.

As in cases described above, a controller 153 is needed to accomplishcommunication between the memory structure of the "flash card" and bus89. Controller 153 communicates with "flash card" unit 151 over lines155 and with connector 33 over lines 157. There may optionally be anopening 159 in case 149 and a connector (not shown) within unit 151 forinserting and withdrawing flash cards, so relatively large collectionsof data may be plugged in as desired. Alternatively the interface may bethe modular interface afforded by the plug-in module 147. Again, giventhe known characteristics of the flash card and of bus 89,implementation of the controller is a matter within the skill of workersin the art.

FIG. 11 shows a LAN module 161 plugged into connector 33 of a notebookcompleter according to an embodiment of the present invention. In theembodiment shown in FIG. 11 a conventional LAN card, such as an Ethernetcard, is mounted in a case 163 to be compatible with plugging into amodule bay of a notebook computer according to an embodiment of thepresent invention.

LAN card 167 communicates with a conventional connector 165 in the faceof the case of module 161 that, is exposed when the module is pluggedinto a bay. This is a conventional connector of the sort known in theart for connecting computers on a network.

Within module 161, in a first, alternative, conventional LAN card 167interfaces to a controller 169 communicating over lines 171 and 173, andthe controller translates between bus 89 and the conventional LAN card.In a second alternative, a LAN card is provided with the translationbuilt in, so no separate controller is needed. The first alternative ispreferable.

FIG. 12 shows a modem module 175 plugged into connector 33 in a bay of anotebook computer according to an embodiment of the present invention.Modem module 175 comprises a conventional modem card 181 mounted in acase 177 to be compatible with plugging into a module bay. In this case,and other cases above, where the term "conventional" is used inconjunction with a card or unit, it is meant that the circuitry andfunction is conventional. The size may be adjusted to be compatible witha module case for plugging into a bay of a notebook computer accordingto the present invention.

Modem card 181 connects over lines 183 to a telephone interface 179,which may comprise more than one "jack" so a hand set may also beconnected. Card 181 communicates to Notebus 89 over lines 187 and 189through controller 185, which translates between the conventional cardand the compressed bus. Alternatively, the translation components may heimplemented on a single card along with the modem circuitry.

FIG. 13 shows a FAX module 191 plugged into connector 33 of a module bayin an embodiment of the present invention. Module 191 comprises aconventional FAX card 199 mounted in a case 193 to be compatible withplugging into a module bay in the present invention. Fax card 199communicates over lines 197 with a telephone interface 195, which may,as in the case of the modem module described above, have more than asingle telephone "jack".

A controller 201 provides an interface for the conventional FAX cardbetween the card and Notebus 89 over lines 203 and 205. Alternatively,the controller may be implemented on the same card as the FAX circuitry.In yet another alternative, the FAX capability and the modem capabilitydescribed above may be implemented into a single module.

FIG. 14 shows a specialty data acquisition module 207 plugged intoconnector 33 in a module bay in a notebook computer according to anembodiment of the present invention. Module 207 comprises a circuit card215 mounted in a case 209 to be compatible with plugging into a modulebay. Card 215 communicates over lines 213 to an interface 211 which maycomprise one or several acquisition leads for connecting to outsideequipment. For example, a data module may be provided For following theoutput of the vertical and horizontal sweep of an oscilloscope, andwould have at least two input leads; one for the vertical and one forthe horizontal sweep.

Card 215 communicates over lines 217 to connector 33, hence Notebus 89.The circuitry on card 215 is designed to digitize the input if the inputis analog, and to be compatible with Notebus 89. Given thecharacteristics of signals to be measured and the characteristics ofNotebus 89, implementation of such a card is within the ordinary skillin the art.

The embodiments of the present invention described above relateprimarily to notebook type computers. However, the invention has broaderapplications. The principles of the invention are also applicable toportable computers known as palmtop computers, and further embodimentsare described below.

FIG. 15A is an isometric view of a modular palmtop computer 221according to an embodiment of the invention. Computer 221 isapproximately the size of one-half a standard piece of paper(approximately 5.5 inches by 8.5 inches) and in a preferred embodimentcomprises a planar array of four Personal Computer Memory CardInternational Association (PCMCIA) Type II module bays in a case 223.

In this embodiment case 223 has a combination I/O area 225 implementedon one side of computer 221, comprising a display overlaid with a touchsensitive planar structure. In other embodiments, the display may be aflat-panel display pivoted to the case, or a separate monitor incommunication with case 223. The touch screen provides a "softkey"operation in conjunction with interactive control logic. In a preferredembodiment of the invention, the control logic resides in static ordynamic memory within case 223 but may also be part of an installedPCMCIA-type peripheral. A power unit (not shown) is enclosed within case223 for converting electrical input on a wide variety of standards tothe form required by the computer. For example, there is a port (notshown) for connecting to a standard household outlet, rated at 120 V.,60 Hz, alternating current. The power unit converts the input to outputsas needed by the computer bus and function modules. There are also inputports for 6 V. DC, 12 V. DC, 9 V. DC, and others, and the power unit inone embodiment of the present invention is capable of recognizing theinput characteristics by sampling, and switching to proper onboardcircuitry to utilize the input.

in the embodiment of the invention shown by FIG. 15A, two module bays227 and 229 are provided on one side of case 223. There are two moremodule bays along the other side of the case opposite the module baysshown. In other embodiments bays may open to other edges of the case.The configuration provides a good balance between the need to stay smalland simple, and to also have adequate versatility. In alternativeembodiments other module configurations may be used, such as PCMCIA TypeIII, and others. In the alternative configurations the arrangement ofthe planar array of modules may vary as well.

FIG. 15B is a view of computer 221 in the direction of arrows 15B--15Bof FIG. 15A. I/O area 225 is located on top of case 223. Module bay 227has a set of guide slots 230A and 230B. The guide slots are to positionand guide a PCMCIA module card inserted into the module bay. Each modulebay in this embodiment is configured to PCMCIA dimensional andconnective standards and secures the fitted PCMCIA cards according tothose standards. In this embodiment of the present invention, case 223has bays configured to PCMCIA type 2, revision B standard. In anotherembodiment of the invention, the case may have other types of PCMCIAmodule bays, or bays configured to one or another proprietary standard.

Each module bay has a bus connector, such as connector 231. In thisembodiment, connector 231 is a standard PCMCIA connector that acceptsPCMCIA cards and is electrically connected to the palmtop's internalbus. It will be apparent to those with skill in the art that there are anumber of equivalent ways to connect a function module.

FIG. 16 is a simplified plan sectional view of computer 221 takenaccording to section line 16--16 of FIG. 15B. Frame 228 frames fourPCMClA module bays 222,224, 227 and 229 arranged in a planar array. Aprinted circuit board structure 235 is fastened and positioned down thecenter of frame 228, and connectors 231,232, 234 and 236 are connectedto the printed circuit board structure and present their pin structureoutward toward the respective bay areas. In the presently describedembodiment, the internal connectors are male connectors, but this is nota requirement of the invention.

Slots 230A and 230B serve to guide a PCMCIA-type card into module bay227, and similar slots are located in each of the other module baysshown as dotted lines in the sectional view. A set of three AA batteries237 are located generally in the plane of the module bays and provide aportable power means in one embodiment. In another embodiment, outsidepower sources may power computer 221 as described above.

FIG. 17 is a partial isometric view of a function module 240 accordingto an embodiment the invention, aligned with module bay 227 of computer221. Arrow 241 shows the direction of insertion of the function module.I/0 area 225 is implemented on top of case 223 in a plane parallel withthe plane of the module bays. Module 240 is a Type 2 PCMCIA card and hasa thickness D1. The opening of module bay 227 has width W1 and heightH1. The length of function module 240 is L1. In this embodiment of thepresent invention, these dimensions conform to PCMCIA industrystandards. In an alternative embodiment of the present invention, modulebay 227 may change in dimension to accommodate other standard orproprietary modules.

Module bay 227 engages function module 240 in the full inserted positionaccording to PCMCIA standards. In another embodiment of the invention,detents may be provided similar to those in FIG. 3 for the largernotebook computer embodiment. There are a number of ways known in theart to position and secure a small module. Securing a module may also beaccomplished by other means, such as clamping or wedging and/or closingretaining mechanisms.

FIG. 18 is an enlarged isometric view of function module 240 accordingto Type 2 PCMCIA standards. Back face 252 includes a female connector253 for mating with a male connector positioned in each module bay, suchas connector 231 in FIG. 15B and FIG. 16. Connectors 231 and 253 arePCMCIA connectors and interface according to that industrial standard.Guide 251A and 251B are sized according to the PCMCIA standards.

Function modules are provided in many models capable of a wide range offunctions. For example, computer 221 in one embodiment has no onboardCPU or system memory. These functions are provided by function modulesthat may be inserted in any one of the available module bays. Otherkinds of function modules that may be inserted include I/O systemmodules that provide speech-based, pen-based or keyboard based input.There are also floppy-disk drives, hard-disk drives, flashcard memorymodules, LAN and modem adapters, Fax modules, specialty modules such asdata acquisition modules adapted to specific equipment, specialty videomodules, modules to adapt scanner periherals to the computer, telephoneadapters, and more. In the case of I/O modules, necessary software, andin some cases firmware and hardware, may be connected to the internalbus structure by the insertion of a module. For example, a module isprovided in one embodiment comprising an induction coil and a controllerfor decoding signals received via a varying magnetic field and providingcode to the computer's internal bus. The varying magnetic field isproduced by a stand-alone keyboard wherein the keystrokes are coded andtransmitted as signals on the field.

In another embodiment, a similar module provides for communication froman auxiliary pen-based input pad. In yet another embodiment, a plug-innodule provides a microphone, DSP circuitry, and necessary software toaccept input from a user by voice, and to convert the voice input tomachine-readable code. Provision of the necessary software and circuitryin these instances in module form provides for maximum flexibility anupgradability for modular systems according to the invention.

Electronic Architecture

FIG. 19 is a block diagram showing internal elements of palmtop computer221, connected to show the electronic architecture of the modularcomputer according to an embodiment of the invention. A power inputand/or conversion unit 257 is housed in case 223 (FIG. 15A) and hasports 259 for power inputs. Power input may be from AA batteries 237(FIG. 16) or from an optional conversion unit via outside electricalsources. Conversion unit 257 senses the input conditions and selectsappropriate circuitry to convert the input to the voltages needed topower the elements of the system. Output from the conversion unit is tobus 255, which comprises paths for power as well as for digitalinformation such as data and addresses.

Because there are a wide variety of function modules, as indicated aboveand described in more detail below, there needs typically to be morethan one power line in bus 255. For example, computer 221 may utilizehard disk drive modules, and these modules are preferably providedwithout onboard power sources. The motor drive for a hard disk requiresa different power configuration (voltage and current) than does a CPU,for example, so there may be parallel power lines of differing size andvoltage level in bus 255. Bus 255 may have a line for 24 V PC, anotherfor 12 V DC, and yet another for 5 V DC, as well as perhaps multipleground lines.

Bus 255 connects I/O area 225 and transmits video signals from a videocontroller. The video controller may be integral to a function module,which is shown as video controller 301 in a CPU function module 300, orimplemented in the case, shown as optional video controller 301(a). Asdescribed above in a preferred embodiment of the present invention, I/Oarea 225 is a combination display with an overlaid touch sensitivescreen. In another aspect, the I/O area may comprise an active-matrixdisplay, in which case, dedicated analog driver lines from videocontroller 301 connect to the display. I/O area 225 may also comprise aconventional LCD display wherein I/O control logic is a function of aninstalled and dedicated I/O peripheral modules. In an alternativeembodiment, video controller 301 is built into case 223 (FIG. 15A), andconnected directly to bus 255, similar to the modular notebook computerdescribed above.

Bus 255 connects to each of module bays 222, 224, 226 and 227 (FIG. 16)through connectors 232, 234, 236 and 231. When a function module, suchas CPU module 300, is inserted into a module bay, female connector 253(FIG. 18) mates with the respective male connector 232 located in thatmodule bay, and circuitry inside the CPU module is then connected to bus255.

Palmtop Function CPU Module

The onboard video controller 301 built into CPU function module 300 is aunique feature in one aspect of the present invention. A user isprovided an ability to tailor the CPU power and type of video controllerto the other modules and applications for palmtop computer 221. Thisprovides a simple means for upgrading by switching CPU function modules.Video signals are local to the CPU, which increases system performance.

FIG. 20 is a more detailed diagram of CPU module 300 for computer 221.CPU module 300 is similar in function to CPU module 99 (FIG. 6), exceptfor the addition of video controller 301. Onboard video controller 301is bus connected by line 263 to a state translator 266. In thisembodiment of the invention, the state translator is configured totransmit and receive video signals and commands over bus 255 viaconnector 231 as well as other functions as described above.

Other Aspects and Features

The embodiments of the present invention described above specificallyaddress notebook-type and. palmtop-type computers. The embodimentdescribed below addresses yet another aspect of the palmtop typecomputers.

FIG. 21 is an isometric drawing of another embodiment of the presentinvention. Computer 400 comprises an attached pivotable display case 401and a fixed keyboard 403. The display case rotates about a hinge 405 andcloses in a fixed detented position above the keyboard. Display case 401comprises a flat-panel display 407. There are two PCMCIA-type modulebays 412A and 412B on one side of the case, and two more (not shown) onthe side opposite. The four PCMCIA module bays are arranged in a planararray as described above. A frame 415 contains a bus structure (notshown) that interconnects all aspects of the PCMCIA type module bays tocomputer 400 as described above. In this embodiment of the presentinvention, a standard keyboard controller (not shown) enclosed in frame415 connects keyboard 403 to the internal bus structure.

It will be evident to one with skill in the art that there are manychanges that might be made without departing from the spirit and scopeof the invention. Many of these alternatives have been described above.For example, there may be more than the four module bays described, orfewer. There may also be more than one planar array of module bays. Toprovide more docking bays in a compact arrangement, one might providetwo or more planar levels, with multiple docking bays in each plane.Similarly, there are many ways modules may be built to be docked in aframework such as computer 11, 221 and 400 to form a planar array. Thereare similarly many different kinds of connectors that might be utilizedas well as many kinds of compressed buses that can be used. There aremany kinds of modules that may be provided, and many other changes thatmight be made within the spirit and scope of the invention.

What is claimed is:
 1. A modular computer comprising:a case havingcontiguous walls, the case for supporting and enclosing elements of themodular computer; a plurality of separate module bays in a common plane,each module bay comprising a walled cavity in the case having an openoutboard end and an inboard end closed by an end wall, wherein the wallsof each cavity, including the end wall, comprise an extension of thecontiguous walls of the case; a multi-pin electrical connector mountedthrough the inboard wall of each module bay; an internal bus within thecontiguous walls of the case connected to each of the electricalconnectors mounted through the inboard walls of the module bays; adisplay; and an input apparatus attached to the case substantiallycoplanar with the plane of the module bays.
 2. A modular computer as inclaim 1 wherein each module bay is sized to receive within the cavityand dock a functional module, and wherein each module bay has guides forengaging mating guides on a functional module.
 3. A modular computer asin claim 1 wherein the input apparatus is a keyboard and the display isa flat-panel display pivoted to the case and closable over the keyboardfor storage and transport.
 4. A modular computer as in claim 1 whereinthe internal bus is a compressed bus for multiplexing data and addresseson a common set of conductors.
 5. A modular computer as in claim 1wherein the module bays open to two opposite edges of the case, and theinternal bus is implemented in a central spine between the inboard wallsof opposite module bays.
 6. A modular computer as in claim 5 comprisingfour module bays, two module bays opening to each of the opposite edgesof the case.
 7. A modular computer as in claim 1 wherein the module baysopen to adjacent edges of the case.
 8. A modular computer as in claim 1further comprising a CPU function module having a CPU microprocessor,wherein, upon docking, the CPU microprocessor becomes the CPU of themodular computer.
 9. A modular computer as in claim 8 further comprisinga video controller and a random access memory connected to the CPUmicroprocessor.
 10. A modular computer as in claim 1 further comprisingan input control function module configured for receiving input signalsfrom a separate input apparatus.
 11. A modular computer as in claim 10wherein the separate input apparatus is a keyboard, and the inputfunction module is configured to receive keystroke signals from thekeyboard and to communicate the keystroke signals to the internal bus.12. A modular computer as in claim 10 wherein the input function moduleis configured to receive input signals from a pen-pad separate inputdevice, and to transmit the input signals to the internal bus.
 13. Amodular computer as in claim 10 wherein the input function modulecomprises a microphone and a digital signal processor for receivingvoice input, converting the voice input to computer-operable code, andtransmitting the computer operable code to the internal bus.
 14. Amodular computer as in claim 1 further comprising an input/outputcontrol function module, the input/output control function moduleconfigured as one of a serial telephone modem, a LAN modem, a floppydisk drive, a hard disk drive, a FAX modem, and a data acquisitionmodem.